The instability of graded structure: implications for the nature of concepts

After a brief introduction to graded structure, this chapter reviews empirical findings showing that the graded structure of a category is unstable, varying widely across contexts. Implications of these findings for theories of categorization are discussed, and it is concluded that graded structures do not represent invariant structural characteristics of Categories. Instead it is proposed that in stability in graded structure occurs because different concept temporarily represent the same categoy in working memory on different occasions.Rather than being retrieved as static units from memory to represent categories, concepts originate in a highly flexible process that retrieves generic and episodic information from long-term memory to construct temporary concepts in Work-ing memorу. Because this concept construction process is highly constrained by goals, context, and jecent experience, the same concept is rarely if ever constructed for a category. A theory of concept construction is presented, and the relations of this theory to dreaming (Foulkes 1985), conceptual combination (Hampton in press a,b; Smith & Osherson 1984), exemplar theories (Brooks 1978; Jacoby & Brooks .1984; Media & Schaeffer 1978), norm theory (Kaimeman &: Miller, 1986), and parallel distributed processing (McClelland & Rumelhart 1986; Rumelhart & McClelland, 1986) are discussed.

[1]  Edward E. Smith,et al.  On the adequacy of prototype theory as a theory of concepts , 1981, Cognition.

[2]  J. Hampton.  Polymorphous Concepts in Semantic Memory , 1979 .

[3]  Dale T. Miller,et al.  Norm theory: Comparing reality to its alternatives , 1986 .

[4]  C. Cherniak.  Prototypicality and deductive reasoning , 1984 .

[5]  A. L. Glass,et al.  Alternate conceptions of semantic memory , 1975 .

[6]  E. Rosch,et al.  Categorization of Natural Objects , 1981 .

[7]  W. Holtzman.  Fundamental statistics in psychology and education. , 1951 .

[8]  Francis S. Bellezza,et al.  Reliability of retrieval from semantic memory: Information about people , 1984 .

[9]  Patrick Henry Winston,et al.  The psychology of computer vision , 1976, Pattern Recognit..

[10]  William Bechtel,et al.  Realism, Instrumentalism, and the Intentional Stance , 1985, Cogn. Sci..

[11]  L. Rips.  Inductive judgments about natural categories. , 1975 .

[12]  Lance J. Rips,et al.  Memory for routines , 1982 .

[13]  L. Barsalou,et al.  The roles of automatic and strategic processing in sensitivity to superordinate and property frequency , 1986 .

[14]  Marvin Minsky,et al.  A framework for representing knowledge , 1974 .

[15]  L. Barsalou.  Ideals, central tendency, and frequency of instantiation as determinants of graded structure in categories. , 1985, Journal of experimental psychology. Learning, memory, and cognition.

[16]  M. McCloskey,et al.  Decision processes in verifying category membership statements: Implications for models of semantic memory , 1979, Cognitive Psychology.

[17]  L. Barsalou,et al.  Contrasting the representation of scripts and categories , 1985 .

[18]  Douglas L. Medin,et al.  Context theory of classification learning. , 1978 .

[19]  R. Mccall,et al.  Fundamental statistics for psychology , 1972 .

[20]  Mark W. Altom,et al.  Correlated symptoms and simulated medical classification. , 1982, Journal of experimental psychology. Learning, memory, and cognition.

[21]  E. Rosch,et al.  Relationships among goodness-of-example, category norms, and word frequency , 1976 .

[22]  E. Rosch.  Cognitive Representations of Semantic Categories. , 1975 .

[23]  Lawrence W. Barsalou,et al.  Constructing Representations of Categories from Different Points of View , 1984 .

[24]  C. Mervis,et al.  Acquisition of basic object categories , 1980, Cognitive Psychology.

[25]  Francis S. Bellezza,et al.  Reliability of retrieval from semantic memory: Noun meanings , 1984 .

[26]  Mark H. Ashcraft,et al.  Property norms for typical and atypical items from 17 categories: A description and discussion , 1978 .

[27]  E. Rosch.  ON THE INTERNAL STRUCTURE OF PERCEPTUAL AND SEMANTIC CATEGORIES1 , 1973 .

[28]  Francis S. Bellezza,et al.  Reliability of retrieval from semantic memory: Common categories , 1984 .

[29]  Edward E. Smith,et al.  Concepts and concept formation. , 1984, Annual review of psychology.

[30]  G. Bower,et al.  Storage and later recognition of exemplars of concepts , 1973 .

[31]  Benjamin Cohen,et al.  Models of Concepts , 1984, Cogn. Sci..

[32]  Edward E. Smith,et al.  Correlated properties in natural categories , 1984 .

[33]  L. Barsalou.  Context-independent and context-dependent information in concepts , 1982, Memory & cognition.

[34]  Eleanor Rosch,et al.  Principles of Categorization , 1978 .

[35]  Edward E. Smith,et al.  Gradedness and conceptual combination , 1982, Cognition.

[36]  Sharon Lee Armstrong,et al.  What some concepts might not be , 1983, Cognition.

[37]  M. McCloskey,et al.  Natural categories: Well defined or fuzzy sets? , 1978 .

[38]  Gregory V. Jones.  Stacks not fuzzy sets: An ordinal basis for prototype theory of concepts , 1982, Cognition.

[39]  J. Hampton.  An investigation of the nature of abstract concepts , 1981, Memory & cognition.

[40]  D. Medin,et al.  The role of theories in conceptual coherence. , 1985, Psychological review.

[41]  Steven M. Smith,et al.  Type I rehearsal: Maintenance and more , 1977 .

[42]  Marvin Minsky,et al.  A framework for representing knowledge" in the psychology of computer vision , 1975 .

[43]  D. Foulkes.  Dreaming: A Cognitive Psychological Analysis , 1985 .

[44]  A. E. Maxwell,et al.  Fundamental statistics in psychology and education , 1943 .

[45]  L. Barsalou,et al.  Ad hoc categories , 1983, Memory & cognition.

[46]  R. Klatzky,et al.  Semantic factors in cognition , 1978 .

[47]  J. Deese.  The structure of associations in language and thought , 1966 .

[48]  F. Craik,et al.  The role of rehearsal in short-term memory , 1973 .

[49]  Lance J. Rips,et al.  Semantic distance and the verification of semantic relations , 1973 .